This report documents the results of a computational study done to compute the inviscid longitudinal aerodynamic characteristics of the Space Shuttle Orbiter for Mach numbers 10 and 15 at angles of attack of 40, 50, 55, and 60 degrees. These computations were done to provide limited aerodynamic data in support of the Orbiter contingency abort task. The Orbiter had all the control surfaces in the undeflected position. The unstructured grid software FELISA was used for these computations with the equilibrium air option. Normal and axial force coefficients and pitching moment coefficients were computed. The hinge moment coefficients of the body flap and the inboard and outboard elevons were also computed. These results were compared with Orbiter Air Data Book (OADB) data and those computed using GASP. The comparison with the GASP results showed very good agreement in Cm and Ca at all the points. The computed axial force coefficients were smaller than those computed by GASP. There were noticeable differences between the present results and those in the OADB at angles of attack greater than 50 degrees.